Avoid using timing related hacks to detect the end of a live resize on macOS

Since cocoa provides start/end notifications for live resizing, rely on
those instead.

glfw/cocoa_window.m

@@ -592,6 +592,17 @@ static GLFWapplicationshouldhandlereopenfun handle_reopen_callback = NULL;
     return YES;
 }
 
+- (void) viewWillStartLiveResize
+{
+    _glfwInputLiveResize(window, true);
+}
+
+- (void)viewDidEndLiveResize
+{
+    _glfwInputLiveResize(window, false);
+}
+
+
 - (BOOL)wantsUpdateLayer
 {
     return YES;

glfw/glfw3.h

@@ -1474,6 +1474,8 @@ typedef void (* GLFWkeyboardfun)(GLFWwindow*, int, int, int, int, const char*, i
  */
 typedef void (* GLFWdropfun)(GLFWwindow*,int,const char**);
 
+typedef void (* GLFWliveresizefun)(GLFWwindow*, bool);
+
 /*! @brief The function signature for monitor configuration callbacks.
  *
  *  This is the function signature for monitor configuration callback functions.
@@ -4343,6 +4345,7 @@ GLFWAPI GLFWscrollfun glfwSetScrollCallback(GLFWwindow* window, GLFWscrollfun cb
  *  @ingroup input
  */
 GLFWAPI GLFWdropfun glfwSetDropCallback(GLFWwindow* window, GLFWdropfun cbfun);
+GLFWAPI GLFWliveresizefun glfwSetLiveResizeCallback(GLFWwindow* window, GLFWliveresizefun cbfun);
 
 /*! @brief Returns whether the specified joystick is present.
  *

glfw/internal.h

@@ -419,6 +419,7 @@ struct _GLFWwindow
         GLFWscrollfun           scroll;
         GLFWkeyboardfun         keyboard;
         GLFWdropfun             drop;
+        GLFWliveresizefun       liveResize;
     } callbacks;
 
     // This is defined in the window API's platform.h
@@ -653,6 +654,7 @@ void _glfwPlatformSetWindowSizeLimits(_GLFWwindow* window,
                                       int maxwidth, int maxheight);
 void _glfwPlatformSetWindowAspectRatio(_GLFWwindow* window, int numer, int denom);
 void _glfwPlatformGetFramebufferSize(_GLFWwindow* window, int* width, int* height);
+void _glfwInputLiveResize(_GLFWwindow* window, bool started);
 void _glfwPlatformGetWindowFrameSize(_GLFWwindow* window,
                                      int* left, int* top,
                                      int* right, int* bottom);

glfw/window.c

@@ -139,6 +139,14 @@ void _glfwInputFramebufferSize(_GLFWwindow* window, int width, int height)
         window->callbacks.fbsize((GLFWwindow*) window, width, height);
 }
 
+// Notifies shared code that a window live resize is in progress
+//
+void _glfwInputLiveResize(_GLFWwindow* window, bool started)
+{
+    if (window->callbacks.liveResize)
+        window->callbacks.liveResize((GLFWwindow*) window, started);
+}
+
 // Notifies shared code that a window content scale has changed
 // The scale is specified as the ratio between the current and default DPI
 //
@@ -1122,6 +1130,17 @@ GLFWAPI GLFWframebuffersizefun glfwSetFramebufferSizeCallback(GLFWwindow* handle
     return cbfun;
 }
 
+GLFWAPI GLFWliveresizefun glfwSetLiveResizeCallback(GLFWwindow* handle,
+                                                              GLFWliveresizefun cbfun)
+{
+    _GLFWwindow* window = (_GLFWwindow*) handle;
+    assert(window != NULL);
+
+    _GLFW_REQUIRE_INIT_OR_RETURN(NULL);
+    _GLFW_SWAP_POINTERS(window->callbacks.liveResize, cbfun);
+    return cbfun;
+}
+
 GLFWAPI GLFWwindowcontentscalefun glfwSetWindowContentScaleCallback(GLFWwindow* handle,
                                                                     GLFWwindowcontentscalefun cbfun)
 {

kitty/child-monitor.c

@@ -808,10 +808,14 @@ process_pending_resizes(double now) {
     for (size_t i = 0; i < global_state.num_os_windows; i++) {
         OSWindow *w = global_state.os_windows + i;
         if (w->has_pending_resizes) {
-            if (now - w->last_resize_event_at >= RESIZE_DEBOUNCE_TIME) update_os_window_viewport(w, true);
-            else {
-                global_state.has_pending_resizes = true;
-                set_maximum_wait(RESIZE_DEBOUNCE_TIME - now + w->last_resize_event_at);
+            if (w->has_live_resize_information) {
+                if (!w->live_resize_in_progress) update_os_window_viewport(w, true);
+            } else {
+                if (now - w->last_resize_event_at >= RESIZE_DEBOUNCE_TIME) update_os_window_viewport(w, true);
+                else {
+                    global_state.has_pending_resizes = true;
+                    set_maximum_wait(RESIZE_DEBOUNCE_TIME - now + w->last_resize_event_at);
+                }
             }
         }
     }

kitty/glfw-wrapper.c

@@ -290,6 +290,9 @@ load_glfw(const char* path) {
     *(void **) (&glfwSetDropCallback_impl) = dlsym(handle, "glfwSetDropCallback");
     if (glfwSetDropCallback_impl == NULL) fail("Failed to load glfw function glfwSetDropCallback with error: %s", dlerror());
 
+    *(void **) (&glfwSetLiveResizeCallback_impl) = dlsym(handle, "glfwSetLiveResizeCallback");
+    if (glfwSetLiveResizeCallback_impl == NULL) fail("Failed to load glfw function glfwSetLiveResizeCallback with error: %s", dlerror());
+
     *(void **) (&glfwJoystickPresent_impl) = dlsym(handle, "glfwJoystickPresent");
     if (glfwJoystickPresent_impl == NULL) fail("Failed to load glfw function glfwJoystickPresent with error: %s", dlerror());
 

kitty/glfw-wrapper.h

@@ -1231,6 +1231,8 @@ typedef void (* GLFWkeyboardfun)(GLFWwindow*, int, int, int, int, const char*, i
  */
 typedef void (* GLFWdropfun)(GLFWwindow*,int,const char**);
 
+typedef void (* GLFWliveresizefun)(GLFWwindow*, bool);
+
 /*! @brief The function signature for monitor configuration callbacks.
  *
  *  This is the function signature for monitor configuration callback functions.
@@ -1791,6 +1793,10 @@ typedef GLFWdropfun (*glfwSetDropCallback_func)(GLFWwindow*, GLFWdropfun);
 glfwSetDropCallback_func glfwSetDropCallback_impl;
 #define glfwSetDropCallback glfwSetDropCallback_impl
 
+typedef GLFWliveresizefun (*glfwSetLiveResizeCallback_func)(GLFWwindow*, GLFWliveresizefun);
+glfwSetLiveResizeCallback_func glfwSetLiveResizeCallback_impl;
+#define glfwSetLiveResizeCallback glfwSetLiveResizeCallback_impl
+
 typedef int (*glfwJoystickPresent_func)(int);
 glfwJoystickPresent_func glfwJoystickPresent_impl;
 #define glfwJoystickPresent glfwJoystickPresent_impl

kitty/glfw.c

@@ -128,6 +128,15 @@ window_iconify_callback(GLFWwindow *window, int iconified UNUSED) {
     global_state.callback_os_window = NULL;
 }
 
+static void
+live_resize_callback(GLFWwindow *w, bool started) {
+    if (!set_callback_window(w)) return;
+    global_state.callback_os_window->has_live_resize_information = true;
+    global_state.callback_os_window->live_resize_in_progress = started;
+    if (!started) request_tick_callback();
+    global_state.callback_os_window = NULL;
+}
+
 static void
 framebuffer_size_callback(GLFWwindow *w, int width, int height) {
     if (!set_callback_window(w)) return;
@@ -610,6 +619,7 @@ create_os_window(PyObject UNUSED *self, PyObject *args) {
     glfwSetWindowIconifyCallback(glfw_window, window_iconify_callback);
     // missing maximize/restore callback
     glfwSetFramebufferSizeCallback(glfw_window, framebuffer_size_callback);
+    glfwSetLiveResizeCallback(glfw_window, live_resize_callback);
     glfwSetWindowContentScaleCallback(glfw_window, dpi_change_callback);
     glfwSetMouseButtonCallback(glfw_window, mouse_button_callback);
     glfwSetCursorPosCallback(glfw_window, cursor_pos_callback);

kitty/state.h

@@ -126,6 +126,7 @@ typedef struct {
     bool is_key_pressed[MAX_KEY_COUNT];
     bool viewport_size_dirty;
     double last_resize_event_at;
+    bool has_live_resize_information, live_resize_in_progress;
     bool has_pending_resizes, is_semi_transparent, shown_once, is_damaged;
     uint32_t offscreen_texture_id;
     unsigned int clear_count;